The present invention relates to a method and a device for ensuring the safety of a low-altitude flight of an aircraft which is guided along a flight trajectory comprising a lateral trajectory and a vertical trajectory.
The present invention applies more particularly, although not exclusively, to a military transport plane that exhibits a low thrust/weight ratio and a high inertia, and whose times for maneuver are generally relatively slow.
As regards the present invention, low-altitude flight is taken to mean flight along a flight trajectory (at low altitude) that allows an aircraft to follow the terrain being overflown as closely as possible, in particular to avoid being detected. Such a low-altitude flight trajectory is therefore situated at a predetermined height from the terrain, for example 500 feet (around 150 meters).
By reason of this proximity to the ground, it is necessary for the flight trajectory to be compatible with the capabilities of the aircraft, that is to say the latter must be able to follow it. Specifically an excessive deviation with respect to this flight trajectory could have catastrophic consequences, with in particular a significant risk of collision with the terrain overflown or with an edifice or an element situated on said terrain.